Maximising profit is not a neutral decision even if it has neutral intentions.
Complaining that for profit companies maximize profit makes about as much sense as complaining great white sharks eat meat. Both do what they were evolved for, both die rather quickly if they don't.
Perhaps we shouldn't put great white sharks in petting zoos. Perhaps we shouldn't put our children's well being into the hands of for profit companies.
You might want to look up "social market economy"[1] and what social democracies in Europe think about the social responsibilities of companies (i.e. that they have those in the first place). I know these are foreign concepts in the US but it's what powers the famous German Mittelstand and our economic stability (though at the cost of missing out on some of the rapid growth possible in the US).
There was no lego for girls, most sets were clearly for boys (via colors and such) and then they made it and it suddenly drove sales big time. It is fair guess that same sets would sell even sooner.
> a certain percentage of parents wouldn't find that feature appropriate or scary or simply not something they would consider as suitable for a toy.
This is true. Large percentage of toy buyers actually, most toys are bought by more distant relatives and friends who prefer to follow all social expectations and wont buy what is not appropriate for gender. Not because they would be evil, but because basically just want to be done with selection quickly and simply and then go their way.
It probably had nothing to do with sexism per se; rather it probably was a business call made by people who suspected that while some percentage of girls would like that feature, a certain percentage of parents wouldn't find that feature appropriate or scary or simply not something they would consider as suitable for a toy. These people are paid to know their target demographic and to make choices that maximize profit for any given product.
Their assumptions might be rooted in sexism, but I suspect that most of their frame of reference consists of simply knowing how parents and relatives view these products, their sexist attitudes included. That is to say, if these people suspect that a significant percentage parents want to stimulate exact thinking and problem solving skills in their girls, they will translate that to market decisions (which is slowly happening now).